In addition to the amount received for the carcasses of animals euthanized or slaughtered, further compensation may be paid to the owners by the Department out of funds appropriated for that purpose at a rate not exceeding that set forth by the U.S. Department of Agriculture, provided that the total amount received by the owner shall not exceed the appraised value of such animal or animals less the amount received for slaughter. Whenever the owner selling an animal that has been condemned is unable to obtain compensation out of state and federal appropriations because of the failure of the purchaser to furnish the seller with such proof of slaughter as may be required, the purchaser shall, in addition to the agreed purchase price, be liable to the seller for the amounts he would otherwise receive out of state and federal appropriations.